Are the sets {0} and `{phi}` empty sets?

Are the sets phi, {0} and {phi} equal or equivalent?

Which of the following sets are empty sets? Justify your answer. (i) A={x : x^(2)=4 and 3x=9} (ii) The set of all triangles in a plane having the sum of their three angles less than 180.

Number of mappings from an empty set to a non empty set with n elements

If P(a) denotes the Power set A and A is void set, then n(P(P(P(a)))) is:

Find sets A, B and C such that A cap B, B cap C and A cap C are non-empty sets and A cap B cap C= phi .

Which of the following is empty set?

Given the sets A = {1, 3, 5}, B = {2, 4, 6} and C = {0, 2, 4, 6, 8} , which of the following may be considered as universal set (s) for all the three sets A, B and phi

If S is the set of distinct values of ' b for which the following system of linear equations x+y+z=1 x+a y+z=1 a x+b y+z=0 has no solution, then S is : a finite set containing two or more elements (2) a singleton an empty set (4) an infinite set

State whether each of the following statements are true or false. If the statement is false, rewrite the given statement correctly. (i) If P= {m, n} and Q = {n, m}, then P xx Q= {(m, n),(n, m)}. (ii) If A and B are non-empty sets, then A xx B is a non-empty set of ordered pairs (x, y) such that x in A and y in B. (iii) If A={1,2}, B={3,4} then A xx (B cap phi)=phi